The present invention relates to novel fungicidal compositions comprising a 2-imidazolin-5-one, which are intended in particular for protecting crops. The invention also relates to a process for protecting crops against fungal diseases.
Compounds derived from 2-imidazolin-5-ones with fungicidal action are known, in particular from European patent application EP 551,048, these compounds making it possible to prevent the growth and development of phytopathogenic fungi which attack or are liable to attack crops.
International patent application WO 96/03044 also discloses a certain number of fungicidal compositions comprising a 2-imidazolin-5-one in combination with one or more fungicidal active materials.
However, it is always desirable to improve the products which can be used by growers in order to combat fungal diseases of crops, and in particular mildews.
It is also always desirable to reduce the doses of chemical products spread into the environment to combat fungal attacks on crops, in particular by reducing the application doses of the products.
Lastly, it is always desirable to increase the number of antifungal products available to growers in order that they will find, among these products, the one which is best suited to the grower""s specific use.
One aim of the invention is thus to provide a novel fungicidal composition which is useful for the problems outlined above.
Another aim of the invention is to propose a novel fungicidal composition which is useful in the preventive and curative treatment of Solanacea diseases.
Another aim of the invention is to propose a novel fungicidal composition which is of improved efficacy against mildew and/or early blight in Solanaceae.
Another aim of the invention is to propose a novel fungicidal composition which is of improved efficacy against mildew and/or oidium and/or botrytis in grapevine.
It has now been found that these aims may be achieved, partly or totally, by means of the fungicidal compositions according to the present invention.
The subject of the present invention is thus, firstly, fungicidal compositions comprising a compound (I) of formula: 
in which:
M represents an oxygen or sulphur atom;
n is an integer equal to 0 or 1;
Y is a fluorine or chlorine atom or a methyl radical;
and a compound (II) chosen from the group comprising:
compound (IIA) or propamocarb, also known as propyl 3-(dimethylamino)propyl carbamate;
a compound (IIB) of formula (IIB) 
xe2x80x83in which:
R1 is a nitrogen atom or the xe2x80x94CH group, and
R2 is a thiomethyl SCH3 group or a diethylamino N(C2H5)2 group,
the compound (IIC) or cyprodinil, also known as 2-phenylamino-4-cyclopropyl-6-methyl-pyrimidine;
the compound (IID), which is 2-hydroxybenzoic acid or salicylic acid, its esters and its salts, in particular the alkali-metal and alkaline-earth metal salts;
the compound (IIF) or 8-t-butyl-2-(N-ethyl-N-n-propylamino)methyl-1,4-dioxaspiro[4.5]decane, also known as spiroxamine;
the compound (IIG) or isopropyl ester of [2-methyl-1-(1-p-tolylethylcarbomyl)propyl] acid, also known as fencaramide;
the compound (IIH) or 4-chloro-2-cyano-1-dimethylsulphamoyl-5-(4-methylphenyl)imidazole;
the compound (I)/compound (II) ratio being between 0.01 and 50, preferably between 0.1 and 10.
It is clearly understood that the said fungicidal compositions may contain a single compound (II) or more than one such compound, for example 1, 2 or 3 compounds (II) depending on the use for which they are intended.
The composition according to the invention are advantageous for combating, in particular, mildews of the Solanaceae, such as potatoes or tomatoes, as well as for combating mildew and oidium of grapevine.
Compound (I) is known, in particular from patent application EP 629,616.
Compound (IIA), or propamocarb, is a fungicide described in the Pesticide Manual 10th Edition, published by the British Crop Protection Council page 843.
Compound (IIB) and its use are known in particular from European patent applications EP 313,512, EP 420,803 and EP 690,061.
Compound (IIC), or cyprodinil, is described in European patent application EP 310,550.
Compound (IIF) and its use as a fungicide are described in European patent application EP 0,281,842.
Compound (IIG) and its use as a fungicide are described in at least one of the European patent applications EP 0,398,072 or EP 0,472,996.
Compound (IIH) and its use as a fungicide are described in at least one of the European patent applications EP 0,298,196 or EP 0,705,823.
The compound (I)/compound (II) ratio is defined as being the ratio of the weight of these 2 compounds. This is likewise the case for any ratio of 2 chemical compounds, mentioned below in the present text, insofar as a definition different from this ratio is not expressly indicated.
These compositions generally appreciably improve the respective and isolated action of compound (I) and of compound (II) for a certain number of fungi that are particularly harmful in crops, in particular for Solanaceae, more particularly for mildew of Solanaceae while at the same time retaining an absence of phytotoxicity towards these crops. This therefore results in an improvement in the spectrum of activity and the possibility of decreasing the respective dose of each active material used, the latter quality being particularly advantageous for readily appreciated ecological reasons.
The fungicidal compositions according to the invention for which the compound (I) is the compound of formula (I) in which M is a sulphur atom and n is equal to 0, also known as (4S)-4-methyl-2-methylthio-4-phenyl-1-phenylamino-2-imidazolin-5-one, are preferred.
In the compositions according to the invention, the compound (I)/compound (II) ratio is advantageously chosen so as to produce a synergistic effect. The term synergistic effect is understood to refer in particular to that defined by Colby S. R. in an article entitled xe2x80x9cCalculation of the synergistic and antagonistic responses of herbicide combinationsxe2x80x9d published in the journal Weeds, 1967, 15, p. 20-22. The said article uses the formula:
E=X+Yxe2x88x92XY/100
in which E represents the expected percentage of inhibition of the disease for the combination of the two fungicides at defined doses (for example equal to x and y respectively), X is the percentage of inhibition observed for the disease by the compound (I) at a defined dose (equal to x), Y is the percentage of inhibition observed for the disease by the compound (II) at a defined dose (equal to y). When the percentage of inhibition observed for the combination is greater than E, there is a synergistic effect.
The term synergistic effect is also understood to refer to that defined by application of the Tammes method, xe2x80x9cIsoboles, a graphic representation of synergism in pesticidesxe2x80x9d Netherlands Journal of Plant Pathology, 70 (1964), p. 73-80.
The ranges of the compound (I)/compound (II) ratio indicated above do not in any way limit the scope of the invention, but are rather mentioned as a guide, a person skilled in the art being entirely capable of carrying out complementary tests in order to find other values of the ratio of doses of these 2 compounds for which a synergistic effect is observed.
According to a first preferred variant of the compositions according to the invention, the compound (II) is chosen from the group comprising compounds (IIA), (IIB), (IIC) and (IID). These compositions in particular have advantageous synergistic properties.
According to a more preferred aspect of this first variant of the compositions according to the invention, the compound (II) is compound (IIA) or propamocarb. In this case, particularly improved protection against mildew of Solanaceae is obtained.
In a preferred manner, when the compound (II) is propamocarb, the compound (I)/compound (II) ratio is between 0.01 and 10, preferably between 0.05 and 1 and even more preferably between 0.1 and 1.
According to another more preferred aspect of this first variant of the compositions according to the invention, the compound (II) is compound (IIB).
In this case, the compound of formula (IIB) in which R1 represents xe2x80x94CH and R2 represents xe2x80x94SCH3 is more particularly preferred. The latter compound is the S-methyl ester of 1,2,3-benzothiadiazole-7-carbothioic acid (also known as CGA 245704).
According to another aspect of the first variant of the compositions according to the invention, the compound (II) is compound (IID).
In a preferred manner, when the compound (II) is compound (IIB) or (IID), the compound (I)/compound (II) ratio is between 0.05 and 50, preferably between 0.1 and 10 and even more preferably between 0.1 and 5.
According to another aspect of the first variant of the compositions according to the invention, the compound (II) is compound (IIC).
In a preferred manner, when the compound (II) is compound (IIC), the compound (I)/compound (II) ratio is between 0.05 and 50, preferably between 0.1 and 10 and even more preferably between 0.2 and 1.
According to a third variant of the compositions according to the invention, the compound (II) is compound (IIF).
When the compound (II) is compound (IIF), the compound (I)/compound (II) ratio is preferably between 0.05 and 10, preferably between 0.1 and 5.
According to a fourth variant of the compositions according to the invention, the compound (II) is compound (IIG).
When the compound (II) is compound (IIG), the compound (I)/compound (II) ratio is preferably between 0.25 and 5, preferably between 0.5 and 4.
According to an even more preferred embodiment of the compositions according to the invention, they advantageously comprise, in the latter case, besides the compounds (I) and (IIG), a compound (IIGxe2x80x2) chosen from:
the salts of a monoalkyl phosphite and of a mono-, di- or trivalent metal cation, such as fosetyl-Al, or
phosphorous acid and its alkali-metal or alkaline-earth metal salts.
The (IIG)/(IIGxe2x80x2) molar ratio of the compounds (IIG) and (IIGxe2x80x2) is generally between 0.037 and 0.37, preferably between 0.018 and 1.8. For the purposes of the present invention, the expression (IIG)/(IIGxe2x80x2) molar ratio is understood to refer to the ratio calculated in the following way. The numerator of this ratio is equal to the number of moles of the compound (IIG). The denominator of this ratio is equal to the number of moles of the compound (IIGxe2x80x2) multiplied by the number of moles of phosphorous acid resulting from the hydrolysis of one mole of compound (IIGxe2x80x2). Phosphorous acid is the compound of empirical formula H3PO3.
Fosetyl-Al is preferably used as compound (IIGxe2x80x2). The (IIG)/(IIGxe2x80x2) weight ratio of the compounds (IIG) and (IIGxe2x80x2) is, in this case, between 0.01 and 1, preferably between 0.05 and 5.
According to a fifth variant of the compositions according to the invention, the compound (II) is compound (IIH). In this case, the compound (I)/compound (II) ratio is between 0.05 and 5, preferably between 0.5 and 2.
Besides the compound (I) and the compound (II), the compositions according to the invention comprise an agriculturally suitable inert support and optionally an agriculturally suitable surfactant. In the following text, the term active material denotes the combination of the compound (I) with the compound (II), and the percentages quoted are, except where otherwise mentioned, weight/weight percentages.
In the present description, the term xe2x80x9csupportxe2x80x9d denotes an organic or inorganic, natural or synthetic material with which the active material is combined in order to facilitate its application onto the plant or onto the soil. This support is thus generally inert and should be agriculturally acceptable, in particular on the crop treated. The support may be solid (in particular: clays, natural or synthetic silicates, silica, resins, waxes, solid fertilizers) or liquid (in particular: water, alcohols, ketones, petroleum fractions, aromatic or paraffinic hydrocarbons, chlorohydrocarbons, liquefied gases).
The surfactant may be an emulsifying, dispersing or wetting agent of ionic or nonionic type. Mention may be made, for example, of polyacrylic acid salts, lignosulphonic acid salts, phenolsulphonic or naphthalenesulphonic acid salts, polycondensates of ethylene oxide with fatty alcohols or with fatty acids or with fatty amines, substituted phenols (in particular alkylphenols or arylphenols), salts of sulphosuccinic acid esters, taurine derivatives (in particular alkyltaurates) and phosphoric esters of polyoxyethylated phenols or alcohols. The presence of at least one surfactant is often required since the active material and/or the inert support are not water-soluble and the vector agent for the application is water.
These compositions may also contain other ingredients of any kind such as, for example, protective colloids, adhesives, thickeners, thixotropic agents, penetration agents, stabilizers, sequestering agents, pigments, dyes or polymers.
More generally, the compositions according to the invention may be combined with any solid or liquid additives corresponding to the usual techniques of agrochemical formulation.
The application techniques are well known to those skilled in the art and they may be used without inconvenience in the context of the present invention. Mention may be made, for example, of spraying.
Among the compositions, solid or liquid compositions may be mentioned generally.
As forms of solid compositions, mention may be made of powders for dusting or dispersion (with an active material content which may be up to 100%) and granules, in particular those obtained by extrusion, by compacting, by impregnation of a granular support or by granulation of a powder (the active material content in these granules being between 1 and 80% for the latter cases).
The compositions may also be used in the form of a powder for dusting; a composition comprising 50 g of active material, 10 g of finely divided silica, 10 g of organic pigment and 970 g of talc may thus be used; these constituents are mixed together and ground and the mixture is applied by dusting.
As liquid composition forms or forms intended to constitute liquid compositions during application, mention may be made of solutions, in particular water-soluble concentrates, emulsifiable concentrates, emulsions, concentrated suspensions, aerosols, wettable powders (or powder to be sprayed), pastes and dispersible granules.
The emulsifiable or soluble concentrates usually comprise 10 to 80% of active material, the ready-to-apply emulsions or solutions themselves containing 0.01 to 20% of active material.
For example, in addition to the solvent, the emulsifiable concentrates may contain, whenever necessary, 2 to 20% of suitable additives such as the stabilizers, surfactants, penetration agents, corrosion inhibitors, dyes or adhesives mentioned above.
Starting with these concentrates, emulsions of any desired concentration may be obtained by dilution with water.
The concentrated suspensions, which may also be applied by spraying, are prepared so as to obtain a stable fluid product which does not separate on settling and they usually contain from 10 to 75% of active material, from 0.5 to 15% of surfactants, from 0.1 to 10% of thixotropic agents, from 0 to 10% of suitable additives, such as pigments, dyes, antifoaming agents, corrosion inhibitors, stabilizers, penetration agents and adhesives and, as support, water or an organic liquid in which the active material is sparingly soluble or insoluble: certain solid organic materials or inorganic salts may be dissolved in the support in order to help prevent sedimentation, or as antifreezes for the water.
The wettable powders (or powder to be sprayed) are usually prepared such that they contain 20 to 95% of active material, and they usually contain, in addition to the solid support, from 0 to 5% of a wetting agent, from 3 to 10% of a dispersing agent and, whenever necessary, from 0 to 10% of one or more stabilizers and/or other additives, such as pigments, dyes, penetration agents, adhesives, anticaking agents, etc.
In order to obtain these powders to be sprayed or wettable powders, the active materials are mixed intimately in suitable mixers with additional substances and are ground using mills or other suitable grinders. Powders to be sprayed whose wettability and placing in suspension are advantageous are thus obtained; they may be placed in suspension with water at any desired concentration.
In place of wettable powders, pastes may be prepared. The conditions and modes of preparation and of use of these pastes are similar to those for the wettable powders or powders to be sprayed.
The dispersible granules are usually prepared by agglomeration, in suitable granulation systems, of the compositions of wettable powder type.
As has already been stated, the aqueous emulsions and dispersions, for example the compositions obtained by diluting a wettable powder or an emulsifiable concentrate according to the invention with water, are included within the general scope of the present invention. The emulsions may be of the water-in-oil or oil-in-water type and they may have a thick consistency such as that of a xe2x80x9cmayonnaisexe2x80x9d.
The fungicidal compositions according to the invention usually contain from 0.5 to 95% of the combination of compound (I) and compound (II).
This may be the concentrated composition, that is to say the commercial product combining compound (I) and compound (II). It may also be the dilute composition ready to be applied to the crops to be treated. In the latter case, the dilution with water may be carried out either using a commercial concentrated composition containing compound (I) and compound (II) (this mixture is referred to as the xe2x80x9cready-to-usexe2x80x9d mixture or xe2x80x9cready mixxe2x80x9d), or using a mixture prepared at the time of use (known as the xe2x80x9ctank mixxe2x80x9d) of two commercial concentrated compositions each containing compound (I) and compound (II).
Lastly, the subject of the invention is a process for curatively or preventively combating the phytopathogenic fungi of crops, characterized in that an effective and non-phytotoxic amount of a fungicidal composition according to the invention is applied to the vegetation to be treated.
The phytopathogenic fungi of the crops which may be combated by this process are, in particular, those:
of the group of oomycetes:
of the genus Phytophthora such as Phytophthora infestans (mildew of Solanaceae, in particular late blight of potato or tomato mildew),
of the family of Peronosporaceae, in particular Plasmopara viticola (downy mildew of grapevine), Plasmopara halstedei (sunflower mildew), Pseudoperonospora sp (in particular cucurbit mildew and downy mildew of hop), Bremia lactucae (mildew of lettuce), Peronospora tabacinae (downy mildew of tobacco) and Peronospora parasitica (downy mildew of cabbage),
of the group of adelomycetes:
of the genus Alternaria, for example Alternaria solani (early blight of Solanaceae and in particular of tomato and potato),
of the genus Guignardia, in particular Guignardia bidwelli (black rot of grapevine),
of the genus Oidium, for example powdery mildew of grapevine (Uncinula necator); powdery mildew of leguminous crops, for example Erysiphe polygoni (powdery mildew of Cruciferae); Leveillula taurica, Erysiphe cichoracearum, Sphaerotheca fuligena; (powdery mildew of cucurbits, of composites and of tomato); Erysiphe communis (powdery mildew of beetroot and cabbage); Erysiphe pisi (powdery mildew of pea and alfalfa); Erysiphe polyphaga (powdery mildew of bean and cucumber mildew); Erysiphe umbelliferarum (powdery mildew of umbellifera, in particular of carrot); Sphaerotheca humuli (hop mildew).
The expression xe2x80x9care applied to the vegetation to be treatedxe2x80x9d is understood to mean, for the purposes of the present text, that the fungicidal compositions which form the subject of the invention may be applied by means of various treatment processes such as:
spraying a liquid comprising one of the said compositions onto the aerial parts of the said vegetation,
dusting, incorporation of granules or powders into the soil, watering around the said vegetation and, in the case of trees, injection or sprinkling.
The spraying of a liquid onto the aerial parts of the crops to be treated is the preferred treatment process.
The expression xe2x80x9ceffective and non-phytotoxic amountxe2x80x9d is understood to refer to an amount of composition according to the invention which is sufficient to allow the control or destruction of the fungi present or liable to appear on the crops, this amount entailing no symptoms of phytotoxicity for the said crops. Such an amount is liable to vary within a wide range depending on the fungus to be combated, the type of crop, the climatic conditions and the nature of the compound (II) included in the fungicidal composition according to the invention. This amount may be determined by systematic field trials, which are within the capabilities of those skilled in the art.
Under the usual conditions of agricultural practice, an amount of fungicidal composition according to the invention corresponding to a dose of compound (I) of between 10 and 500 g/ha, preferably between 20 and 300 g/ha, generally gives good results.
When the compound (II) is compound (IIA), the amount of fungicidal composition according to the invention advantageously corresponds to a dose of compound (II) of between 50 and 2500 g/ha, preferably between 200 and 1500 g/ha.
When the compound (II) is compound (IIB), the amount of fungicidal composition according to the invention advantageously corresponds to a dose of compound (II) of between 2 and 100 g/ha, preferably between 100 and 50 g/ha.
When the compound (II) is compound (IIC), the amount of fungicidal composition according to the invention advantageously corresponds to a dose of compound (II) of between 20 and 2000 g/ha, preferably between 100 and 550 g/ha.
When the compound (II) is compound (IID), the amount of fungicidal composition according to the invention advantageously corresponds to a dose of compound (II) of between 20 and 5000 g/ha, preferably between 50 and 1000 g/ha.
When the compound (II) is compound (IIF), the amount of fungicidal composition according to the invention advantageously corresponds to a dose of compound (II) of between 100 and 1000 g/ha, preferably between 300 and 800 g/ha.
When the compound (II) is compound (IIG), the amount of fungicidal composition according to the invention advantageously corresponds to a dose of compound (II) of between 50 and 250 g/ha, preferably between 100 and 200 g/ha.
When the compound (II) is compound (IIH), the amount of fungicidal composition according to the invention advantageously corresponds to a dose of compound (II) of between 100 and 400 g/ha, preferably between 150 and 350 g/ha.
The examples which follow are given purely by way of illustration of the invention, which they do not limit in any way.
In these examples, as well as in the figures to which reference is made, compound (I) is understood to denote (4S)-4-methyl-2-methylthio-4-phenyl-1-phenyl-amino-2-imidazolin-5-one and compound (IIB) is understood to denote the S-methyl ester of 1,2,3-benzothiadiazole-7-carbothioic acid (or CGA 245704). Similarly, compound (IIGxe2x80x2) is understood to refer to Fosetyl-Al.